The purpose of this proposal is to demonstrate the capabilities of the University of Pittsburgh to participate as a Clinical site in a NICHD-sponsored network addressing Preterm Birth in Nulliparous Women (Nullipara Network). Our site has been a long-standing track record of successful contribution to single and multicenter studies of adverse pregnancy outcomes for more than 20 years. We are particularly well suited to be a clinical site in this Network because of our volume, clinical research infrastructure and track record, basic and translational experience and expertise, and specialized resources that we can bring to such a multicenter venture. Approximately 10,000 women deliver per year at Magee-Womens Hospital, and 85% of these women initiate prenatal care in our system at < 10 weeks. Through our extensive research infrastructure, we have successfully enrolled women in the first trimester, followed them longitudinally through pregnancy to delivery, with serial collection and processing of biological samples and ultrasound data. Our research operation is ideal for cohort studies such as that to be conducted by the Nullipara Network. Additionally, our site brings unique content and technical expertise in clinical obstetrics, fetal imaging, genomics and proteomics, placental pathology, and epidemiology. All of these areas represented among our faculty, and we have a long and successful history of productive collaboration. The Nullipara Network is charged with 4 objectives: 7 Determine maternal characteristics that influence and/or predict adverse pregnancy outcome to include genetics, epigenetics, physiological response to pregnancy, and the interaction with environmental exposures 7 Identify specific aspects of placental development and function that lead to adverse pregnancy outcome 7 Characterize genetic, growth, and developmental parameters of the fetus that are associated with adverse pregnancy outcome 7 Determine whether assessments and potential interventions during pregnancy may provide useful information to reduce the incidence of adverse pregnancy outcome Our site has the track record, patient base, research infrastructure, content and technical expertise to design and execute a cohort study that achieves all four of these objectives.